Safety and Immunogenicity of GPO Seasonal Trivalent Inactivated Influenza Vaccine in Healthy Thai Adults

A Phase I/II Randomized Double Blind Controlled Study to Evaluate the Safety and Immunogenicity of GPO Seasonal Trivalent Inactivated Split Virion Influenza Vaccine in Healthy Thai Adults Aged Between 18 Years to 49 Years

The study is aim to evaluate the safety and immunogenicity of one dose (15 μg HA per strain per dose) of the GPO seasonal trivalent inactivated split virion influenza vaccine (Tri Fluvac) in healthy adults aged 18 to 49 years over 90 days post-injection.

This is a double blind randomized study consisting of two phases - Phase I and Phase II. The same vaccine, a seasonal trivalent inactivated split virion influenza vaccine [A/California/7/2009, reassortant virus NYMC X-181 (H1N1), A/Victoria/210/2009, reassortant virus NYMC X-187 (H3N2), and B/Brisbane/60/2008, reassortant virus NYMC BX-35 virus strains] will be given in both Phase I and Phase II of the study.

The vaccine will be administered via the intramuscular route; the preferred injection site will be the deltoid of the non-dominant arm. After vaccination volunteers will remain at the clinic for at least 30 minutes to observe for any reactogenicity after immunization. Total follow-up is 90 days.

Blood specimens will be collected on Day 0 prior to vaccination, Day 21, Day 60, and day 90.

Inclusion Criteria:

• Healthy
• Age 18-49 years old
• Having Thai ID card or equivalent
• All hematology, biochemistry and urine analysis are within normal range or of no clinical significance (not higher than 1.5 time of normal value without any clinical finding from history and physical examination)
• Able to read and write and sign written informed consent form or assent form.

Exclusion Criteria:

• Known history of egg allergy
• Having had recently influenza infection confirmed as H1N1, H3N2, or Flu B within 3 months preceding enrolment to the trial
• Vaccination against influenza in the past 6 months preceding enrolment to the trial
• History of bronchial asthma, chronic lung diseases, chronic rhinitis
• History of immunodeficiency state
• History of immunosuppression < 6 months prior to immunization
• History of anaphylactic or other allergic reactions to influenza vaccine or any vaccine component or excipient (e.g. gentamicin or thimerosal)
• Acute infectious with fever > 38 degree Celsius and noninfectious diseases (within 72 hours) preceding enrollment in the trial
• The volunteers who have been taking immunoglobulin products or have had a blood transfusion during past 3 months before the beginning of the experiment
• Participation in other research study
• Pregnancy or plan to become pregnant for 60 days after enrollment or breast feeding
• Current alcohol abuse or drug addiction that might interfere with the ability to comply with trial procedures
• Any condition that in the opinion of the investigator would pose a health risk to the subject if enrolled, or could interfere with the evaluation of the vaccine